Exploring the effect of cricket (Acheta domesticus)-enriched pasta on gut microbiota after in vitro colonic fermentation

Introduction: Cricket (Acheta domesticus) is a sustainable high-quality protein source that can be incorporated into Western diet in pasta-based products. Although cricket powder is rich in chitin, a potential prebiotic fiber, its effect on gut microbiota remains underexplored. Methodology: Static in vitro colonic fermentation was performed using the non-bioaccessible fractions from simulated gastrointestinal digestion (INFOGEST 2.0) of cricket-enriched pasta (10% A. domesticus powder) and durum wheat pasta, compared with a control (non-bioaccessible fraction of digested Milli-Q water). Fermentation comprising a simple medium, the non-bioaccesible fractions and a pooled fecal inoculum from three healthy donors were incubated under simulated colonic conditions (anaerobiosis, 37 °C, 85 rpm, 20 h; n=3). Bacterial DNA was extracted, the V3–V4 region of 16S rRNA was sequenced (Illumina MiSeq), and α-/β-diversity, taxonomic abundances and differential taxa (LEfSe) were analyzed using MicrobiomeAnalyst. Results and discussion: After fermentation, all substrates showed reduced Bacteroidota and increased Bacillota and Pseudomonadota, consistent with nutrient depletion and metabolite accumulation. Pasta supplementation significantly decreased α-diversity (observed ASVs, Shannon, Simpson) versus the control. β-diversity (PCoA, Bray–Curtis and UniFrac) mainly separated samples by fermentation time, with no clear separation between non-supplemented and pasta-supplemented samples after incubation (PERMANOVA, p>0.05). Nevertheless, LEfSe analysis revealed that both pastas similarly increased the abundance of Acidaminococcus (25–33%), an amino-acid-utilizing butyrate producer, and of Phascolarctobacterium (acetate/propionate producer), reflecting a general substrate response rather than a cricket-specific effect. In contrast, the abundance of Bifidobacterium increased more markedly with cricket-enriched pasta (5% vs. 2%), consistent with its utilization of chitin and chitooligosaccharides from cricket exoskeleton as carbon sources. These shifts could be associated with enhanced short-chain fatty acid production and positive fiber-driven ecosystem modulation. Conclusion: Cricket-enriched pasta produced a slight but favorable gut microbiota modulation, supporting a potential prebiotic effect that requires further research.